A researcher at Yale University is conducting a long-term study with 120 people -- veterans with "intractable cases of PTSD" -- who he thinks can be cured of their dehabilitating condition with marijuana.

Marijuana Cupcake Anyone?

Most people suffering from PTSD go through a regimen of drugs or more-invasive "exposure therapy," in which they dig as deeply as possible into their trauma for 12 weeks. Most drop out in Week 3, according to the report.

The theory of R. Andrew Sewell is that tetrahydrocannabinol, or THC, one of the active ingredients in cannabis, can help the brain learn new information. This in turn helps people suffering from PTSD forget the old -- as in bad -- information.

Cannabis Cup Cake Anyone?

This is called "extinction learning," Sewell says. And such learning is made easier when a "switch" in the brain called CB1 is activated. It turns out cannabis is very good at activating the CB1 receptor.

"We're talking about a cure," said Sewell, who noted that after treatment, no drugs -- not cannabis and not antidepressants -- would be required.